Circular RNA 0001785 regulates the pathogenesis of osteosarcoma as a ceRNA by sponging miR-1200 to upregulate HOXB2

lncRNA IGHCγ1 Acts as a ceRNA to Regulate Macrophage Inflammation via the miR-6891-3p/TLR4 Axis in Osteoarthritis

Accumulating data have implicated that long noncoding RNA (lncRNA) plays an important role in osteoarthritis (OA), which may function as a competitive endogenous RNA (ceRNA) of microRNAs (miRNAs). lncRNA IGHCγ1 has been demonstrated to regulate inflammation and autoimmunity. Nonetheless, the altering effect of IGHCγ1 in OA remains unclear. This study is aimed at investigating the mechanism and function of lncRNA IGHCγ1 in OA. CCK-8, EdU, and transwell assays were used to estimate macrophage proliferation and migration. Fluorescence in situ hybridization (FISH) was performed to estimate the local expression of lncRNA IGHCγ1 in macrophages. Luciferase reporter assay was adopted to validate the ceRNA role of IGHCγ1 as miRNA sponge. lncRNA IGHCγ1 was primarily localized in macrophage cytoplasm and upregulated in OA. miR-6891-3p inhibited macrophage proliferation, migration, and inflammatory response by targeting TLR4, while lncRNA IGHCγ1 promoted TLR4 expression by functioning as a ceRNA for miR-6891-3p through the NF-κB signal in macrophages. This study strongly supports that lncRNA IGHCγ1 regulates inflammatory response via regulating the miR-6891-3p/TLR4/NF-κB axis in macrophages.

LncRNA RGMB-AS1 Promotes Glioma Growth and Invasion Through miR-1200/HOXB2 Axis

Background

Dysfunction of long noncoding RNA (lncRNA) is associated with tumorigenesis of various malignancies, including glioma. LncRNA RGMB-AS1 (RGMB antisense RNA 1) has been reported to participate in initiation and progression of several cancers, such as lung cancer, hepatocellular carcinoma and laryngeal squamous cell carcinoma. Nevertheless, whether RGMB-AS1 regulates glioma development is not investigated. In this study, we aimed to determine its roles in glioma.

Methods

qRT-PCR and Western blotting were used to measure gene expression. CCK8 and colony formation assays were utilized to analyze proliferation. Transwell assay was used to determine cell migration and invasion. Luciferase reporter assay was used to validate the interactions among RGMB-AS1, miR-1200 and HOXB2.

Results

RGMB-AS1 was upregulated in glioma tissues and associated with glioma grade and patients' prognosis. Moreover, RGMB-AS1 silencing significantly inhibited the proliferation, migration and invasion of glioma cells. RGMB-AS1 downregulation led to more tumor cells arrested in the quiescent state. Mechanistically, we found that RGMB-AS1 was a molecular sponge for miR-1200. MiR-1200 level was inhibited by RGMB-AS1. And RGMB-AS1 promoted HOXB2 expression via sponging miR-1200. Restoration of HOXB2 effectively rescued the abilities of proliferation, migration and invasion in RGMB-AS1-depleted glioma cells.

Conclusion

Collectively, our work clarified that RGMB-AS1/miR-1200/HOXB2 signaling exerts an essential role in regulating glioma progression.

Upregulation Of circMMP9 Promotes Osteosarcoma Progression Via Targeting miR-1265/CHI3L1 Axis

Background

Osteosarcoma (OS) is a very aggressive cancer. Nevertheless, how circular RNA (circRNA) contributes to OS progression remains unclear. Here, we aimed to research the functions of circMMP9 in OS progression.

Methods

Gene expression was determined via qRT-PCR. siRNA was used to knock down circMMP9. Proliferation was analyzed using CCK8 and colony formation assays. Migration and invasion were measured using Transwell assay.

Results

circMMP9 was overexpressed in cancer tissues. Overexpressed circMMP9 was correlated with advanced tumor stage and predicted poor prognosis. circMMP9 knockdown exhibited a tumor-suppressive phenotype via suppressing proliferation, migration and invasion. Besides, decreased circMMP9 level promoted OS cellular apoptosis. Mechanistically, circMMP9 was shown to be located in the cytoplasm and sponge miR-1265. Furthermore, miR-1265 directly targeted CHI3L1. CHI3L1 levels were modulated by circMMP9/miR-1265 axis. Rescue experiments indicated that circMMP9 contributes to OS development through the miR-1265/CHI3L1 pathway.

Conclusion

Our findings provide a novel insight about how circRNA regulates OS progression.